LEADTOOLS For .NET Class Library Send comments on this topic. | Back to Introduction - All Topics | Help Version 17.0.3.28
Using the Fast Twain Feature
ScanTutorials Take the following steps to start a project and to add some code that acquires the images using Fast Twain:
  1. Start Visual Studio .NET.
  2. Choose File->New->Project… from the menu.
  3. In the New Project dialog box, choose either "Visual C# Projects" or "Visual Basic Projects" in the Projects Type List, and choose "Windows Application " in the Templates List.
  4. Type the project name as " UsingFastTwainFeature" in the Project Name field, and then choose OK. If desired, type a new location for your project or select a directory using the Browse button, and then choose OK .
  5. In the "Solution Explorer" window, right-click on the "References" folder, and select "Add Reference…" from the context menu. In the "Add Reference" dialog box, select the ".NET" tab and browse to Leadtools For .NET "<LEADTOOLS_INSTALLDIR>\Bin\DotNet\Win32 " folder and select the following DLLs:
    • Leadtools.dll
    • Leadtools.Twain.dll
    • Leadtools.Codecs.dll
    • Leadtools.WinForms.dll
    Click the Select button and then press the OK button to add the above DLLs to the application.
  6. Go to the toolbox (View->Toolbox) and Drag and drop a 2 instance of RadioButton control to the top of the form and set the following properties for them:
    Text Name Checked
    Native radioNative False
    Memory radioMemory False
  7. Go to the toolbox (View->Toolbox) and Drag and drop a 1 instance of Button control to the top of the form and set the following properties for them:
    Text Name
    Fast Acquire buttonFastAcquire
  8. Go to the toolbox (View->Toolbox) and Drag and drop a 1 instance of Check Box control to the top of the form and set the following properties for them:
    Name Name
    Use Buffer Size checkBoxUseBufferSize
  9. Go to the toolbox (View->Toolbox) and Drag and drop a 2 instance of Text Box control to the top of the form and change the following properties:
    Property Value
    Name textBufferSize
    Name textFileName
  10. Switch to Form1 code view (right-click Form1 in the solution explorer then select View Code ) and add the following lines at the beginning of the file:

    [Visual Basic] 

     
            Imports Leadtools
            Imports Leadtools.Twain
            Imports Leadtools.Codecs
            Imports Leadtools.WinForms
    [C#] 
                using Leadtools;
            using Leadtools.Twain;
            using Leadtools.Codecs;
            using Leadtools.WinForms;
  11. Declare the following private variable:

    [Visual Basic] 

     
            Private WithEvents twnSession As TwainSession
    [C#] 
     
            private TwainSession twnSession;
  12. Add an event handler to the Form1 Load event and code it as follows:

    [Visual Basic] 

     
            Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
               Try
                  ' Unlock Document support.
                  ' Note that this is a sample key, which will not work in your toolkit.
                  RasterSupport.Unlock(RasterSupportType.Document, "TestKey")
            
                  twnSession = new TwainSession
                  twnSession.Startup(Me, "manufacturer", "productFamily", "version", "application", TwainStartupFlags.InitializeMultithreaded)
               Catch ex As Exception
                  MessageBox.Show(ex.Message)
               End Try
            End Sub
    [C#] 
     
            private void Form1_Load(object sender, System.EventArgs e)
            {
               try
               {
                  // Unlock Document support.
                  // Note that this is a sample key, which will not work in your toolkit.
                  RasterSupport.Unlock(RasterSupportType.Document, "TestKey");
            
                  twnSession = new TwainSession();
                  twnSession.Startup(this, "manufacturer", "productFamily", "version", "application", TwainStartupFlags.InitializeMultithreaded);
               }
               catch (Exception ex)
               {
                  MessageBox.Show(this, ex.Message);
               }
            }
  13. Add an event handler to the Form1 Closing event and code it as follows:

    [Visual Basic] 

     
            Private Sub Form1_FormClosing(ByVal sender As System.Object, ByVal e As System.Windows.Forms.FormClosingEventArgs) Handles MyBase.FormClosing
               Try
                  twnSession.Shutdown()
               Catch ex As Exception
                  MessageBox.Show(ex.Message)
               End Try
            End Sub
    [C#] 
     
            private void Form1_FormClosing(object sender, FormClosingEventArgs e)
            {
               try
               {
                  twnSession.Shutdown();
               }
               catch (Exception ex)
               {
                  MessageBox.Show(this, ex.Message);
               }
            }
  14. Add an event handler to the buttonFastAcquire Click event and code it as follows:

    [Visual Basic] 

     
            Private Sub buttonFastAcquire_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles buttonFastAcquire.Click
               Dim transferMode As TwainTransferMode
               Dim transferFormat As RasterImageFormat
            
               If radioMemory.Checked Then
                  transferMode = TwainTransferMode.Buffer
                  transferFormat = RasterImageFormat.CcittGroup4
               Else
                  transferMode = TwainTransferMode.Native
                  transferFormat = RasterImageFormat.Tif
               End If
            
               Try
                  twnSession.AcquireFast(textFileName.Text, _
                                         TwainFastUserInterfaceFlags.Show Or TwainFastUserInterfaceFlags.UseThread, _
                                         transferMode, _
                                         transferFormat, _
                                         1, _
                                         True, _
                                         Convert.ToInt32(textBufferSize.Text), _
                                         checkBoxUseBufferSize.Checked)
               Catch ex As Exception
                  MessageBox.Show(ex.Message)
               End Try
            End Sub
    [C#] 
     
            private void buttonFastAcquire_Click(object sender, System.EventArgs e)
            {
               TwainTransferMode transferMode;
               RasterImageFormat transferFormat;
            
               if (radioMemory.Checked)
               {
                  transferMode = TwainTransferMode.Buffer;
                  transferFormat = RasterImageFormat.CcittGroup4;
               }
               else
               {
                  transferMode = TwainTransferMode.Native;
                  transferFormat = RasterImageFormat.Tif;
               }
            
               try
               {
                  twnSession.AcquireFast(textFileName.Text,
                                         TwainFastUserInterfaceFlags.Show | TwainFastUserInterfaceFlags.UseThread,
                                         transferMode,
                                         transferFormat,
                                         1,
                                         true,
                                         Convert.ToInt32(textBufferSize.Text),
                                         checkBoxUseBufferSize.Checked);
               }
               catch (Exception ex)
               {
                  MessageBox.Show(ex.Message);
               }
            }
  15. Build, and Run the program to test it.